Ahead of a Kiwi summer tour, former Australian Idol winner Guy Sebastian talks about charity, babies and his changing faith.

He's worked with some of the world's hottest artists, had a multi-platinum smash and started his own charity. Now Guy Sebastian is bringing his first solo New Zealand tour to our shores, hitting the country's best surf towns over the summer holiday period.

It's been more than a decade since Sebastian triumphed on Australian Idol. Six studio albums later, it's a tour no doubt long awaited by his fans. Sebastian toured here with Lionel Richie a few years ago but this will be his first solo tour with full band and stage production. He says fans can expect a set list featuring a few of his old tracks along with his newer stuff, including upcoming single Like a Drum.

Accompanying Sebastian on tour is former John Mayer guitarist David Ryan Harris, the brains who helped write Sebastian's hit Battle Scars.

"He's ridiculous. I'm a massive fan of his and he's a great friend of mine," Sebastian says.

"He's such a beautiful craftsman of lyrics.

"There's a song he does called Pretty Girl [that] makes you melt, it's a song I wished I had wrote."

Sebastian has come a long way from the song which won fans' hearts, Angels Brought Me Here, but he remains the humble and chatty pop star who graced our screens more than 10 years ago - sans afro.

This year has been a hectic one - emotionally charged single Battle Scars recently reached platinum status in the United States. The success rode on the back of a flurry of hits including Who's That Girl and Like it Like That as he moved towards electronic dance music (EDM).

Like a Drum is similarly up-beat. "I just wanted to come out with something that was going to be a bit more summery and uplifting."

It's a contrast to the heavier themes of Battle Scars, which talks about a relationship breakdown, and Get Along, which Sebastian says looks at "a Eutopian world where we can all co-exist and have respect for each other's beliefs and colours and races."

"I have seen the volatility that can arise with differences of opinion," he says. "Get Along was basically written out of that sadness."

In his homeland, the staunchly Christian musician has been portrayed as ‘losing his religion' over his beliefs on gay marriage as the bill makes its way through Australian Parliament.

He is open about how his fundamental Christian upbringing taught him that his beliefs were right, and everyone else was wrong.

"I was very ignorant," he says.

"One of my best friends ‘came out' and I was forced to ask what do I actually think? My friend basically moved to a whole other country because he was so scared of religious reactions. He fought it for a very long time.

"When it's someone you know, who MC'd your wedding, who was your best man, who you were close to ... that's the first thing that broke my heart, that he was fearful. That's why I wrote Get Along," Sebastian said.

Rather than turn away from his religion, he has portrayed a grittier faith. "I'm a bible-believing Christian, [but] I don't pretend to have all the answers," he says. "My first reaction is love."

In his career, Sebastian has gained the respect of some of America's greatest music heavyweights - collaborating with the likes of Robin Thicke and Lupe Fiasco.

"I'm always hopeful, I think a good song will attract the right rapper," Sebastian said. "Lupe was right for Battle Scars, when I asked him to do it I wasn't even wondering.

"I thought, it's Lupe Fiasco, it's a stab in the dark. He got back to me and said this is the right song, let's get on to it."

The collaboration was a boon, as was Out with my Baby, an Australian number one song he wrote with Blurred Lines singer Thicke.

"Robin Thicke's the quickest writer I've ever worked with," Sebastian says. "He just sings it and it's right. There's not many writers in the world who can do that."

Sebastian's now gunning for collaborations with the likes of California hip hop artist Kendrick Lamar and Canadian rapper Drake.

"I just wrote a song called Lightning. It's a pretty dark song, it needs an aggressive rapper. Then I wrote a song called Light and Shade that's really soulful."

The Sebastians - Guy, wife Jules, son Hudson - have based themselves in LA for the time being, buying a house and filling it with "cots and highchairs and bath toys". They are expecting another child in May. The family have also just set up house in Bondi, Sydney, where surprisingly the hustle and rising house prices make Auckland look like a walk in the park.

It's back home that Sebastian has embarked on another passion.

Dabbling in landscape photography, he recently held his first exhibition to fundraise for the charity he and his wife Jules set up, The Sebastian Foundation.

Media attention has been somewhat sucrose, labelling the couple as the Brad and Angelina from down-under. But perhaps it's a worthy title, considering they hope to open an orphanage one day.

"I guess for years I have met some people who have had some unbelievable highs and some pretty shocking lows. You get this overwhelming sense of wanting to do something," Sebastian says.

"We have just had bush fires here that have affected a lot of people, there are year 12 students who lost a lot of text books. It's the little ways we can help."